Reflection characteristics play a critical role in identifying, assessing, and responding to different types of oil spills. In this paper, we prepared three concentrations of oil-in-water (OW) emulsions and measured their directional reflection properties in the visible and near-IR range. The spectral differences in reflectance between OW emulsions and oil films were analyzed. Furthermore, the AVIRIS and Landsat 7 images collected over the oil spill accident in the Gulf of Mexico were used to demonstrate the feasibility to apply the experimental results in the identification of oil spill types. The results show that OW emulsions and oil films can be well discriminated in remote sensing images based on their reflectance spectral differences. The OW emulsion is mainly distributed in strips along the edge of the oil film, which is useful to delineate the spill outline and calculate the polluted area.